Poly(arylene sulfide) resins have become well known in the art for their thermal resistance, chemical resistance, good overall electrical insulative properties, unusual insolubility and inherent flame resistance. PAS resins can be compounded with fillers and reinforcing fibers to enhance certain of these properties and to provide compounds useful in more specific applications. For example, glass reinforcement of PAS resins produces injection and compression molding compounds which exhibit high tensile strength, high flexural modulus, good flexural strength, high heat deflection temperature, low elongation, and moderate impact strength.
The excellent physical properties of PAS resins make these compounds highly useful in manufacturing articles by injection molding techniques. However, the production of shaped articles from PAS compounds by injection molding can require high mold temperatures and relatively long molding cycle times which require expensive energy expenditures. It would, therefore, be desirable to have a rapidly crystallizable PAS resin so that shorter mold cycle times and/or lower mold temperatures could be utilized to increase profitability.
It is an object of this invention to provide a method of producing a more rapidly crystallizing PAS resin. A further object of this invention is to provide a thermoplastic composition comprising PAS and a poly(styrene sulfonic acid salt) which crystallizes more rapidly. Another object of this invention is to provide a method of increasing the melt crystallization temperature and decreasing the cold crystallization temperature of a PAS resin and therefore broaden the processing window of the PAS resin. By this method, PAS resins are provided which upon injection molding require less energy and time expenditure.
Other objects, aspects, and the several advantages of this invention will be apparent to those skilled in the art upon a study of the specification and the appended claims.